Bioterrorism is a serious threat to modern society.

That virus is posing a great threat to people all over the world.

He said he would expose me to threat.

Terrorism is a major problem threatening peace around the world.

This problem is very serious.

Do you understand the seriousness of this problem?

Modern technology is advancing at an astonishing rate.

We should take responsibility as part of society.

The environmental issues are becoming more serious.

Environmental issues are becoming more serious day by day.